scripts/glibcsymbols.py

   1 #!/usr/bin/python3
   2 # Processing of symbols and abilist files.
   3 # Copyright (C) 2020-2022 Free Software Foundation, Inc.
   4 # This file is part of the GNU C Library.
   5 #
   6 # The GNU C Library is free software; you can redistribute it and/or
   7 # modify it under the terms of the GNU Lesser General Public
   8 # License as published by the Free Software Foundation; either
   9 # version 2.1 of the License, or (at your option) any later version.
  10 #
  11 # The GNU C Library is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 # Lesser General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU Lesser General Public
  17 # License along with the GNU C Library; if not, see
  18 # <https://www.gnu.org/licenses/>.
  19
  20 """Symbol processing for glibc."""
  21
  22 import os
  23
  24 def replace_file(path, new_contents):
  25     """Atomically replace PATH with lines from NEW_CONTENTS.
  26
  27     NEW_CONTENTS must be a sequence of strings.
  28
  29     """
  30     temppath = path + 'T'
  31     with open(temppath, 'w') as out:
  32         for line in new_contents:
  33             out.write(line)
  34     os.rename(temppath, path)
  35
  36 class VersionedSymbol:
  37     """A combination of a symbol and its version."""
  38
  39     def __init__(self, symbol, version):
  40         """Construct a new versioned symbol."""
  41         assert symbol
  42         assert version
  43         self.symbol = symbol
  44         self.version = version
  45
  46     def __str__(self):
  47         return self.symbol + '@' + self.version
  48
  49     def __eq__(self, other):
  50         return self.symbol == other.symbol and self.version == other.version
  51
  52     def __hash__(self):
  53         return hash(self.symbol) ^ hash(self.version)
  54
  55 def read_abilist(path):
  56     """Read the abilist file at PATH.
  57
  58     Return a dictionary from VersionedSymbols to their flags (as
  59     strings).
  60
  61     """
  62     result = {}
  63     with open(path) as inp:
  64         for line in inp:
  65             version, symbol, flags = line.strip().split(' ', 2)
  66             versym = VersionedSymbol(symbol, version)
  67             if versym in result:
  68                 raise IOError("{}: duplicate symbol {}".format(path, versym))
  69             result[versym] = flags
  70     return result
  71
  72 def abilist_lines(symbols):
  73     """Build the abilist file contents (as a list of lines).
  74
  75     SYMBOLS is a dictionary from VersionedSymbols to their flags.
  76
  77     """
  78     result = []
  79     for versym, flags in symbols.items():
  80         result.append('{} {} {}\n'.format(
  81             versym.version, versym.symbol, flags))
  82     result.sort()
  83     return result